From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FB7BC54EEB for ; Mon, 23 Mar 2020 15:01:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 704B2206F8 for ; Mon, 23 Mar 2020 15:01:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727521AbgCWPBL (ORCPT ); Mon, 23 Mar 2020 11:01:11 -0400 Received: from mga02.intel.com ([134.134.136.20]:26774 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727186AbgCWPBK (ORCPT ); Mon, 23 Mar 2020 11:01:10 -0400 IronPort-SDR: wEAdiD36GD9o81KLPyhMEeSrsQluUXcP23V2L6mxkhabW+wYzGKAQwSIoFovzfodU2/k9uJ/qe 8YtuZTMBRW0Q== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Mar 2020 08:01:09 -0700 IronPort-SDR: xOQfy8K5XD/GBlZ7JKWStXexCAJb8C+lZtzN2pJK44cWveY8AhNgNESDv/BIFavzGK8p1xtQ9G 86unrakaIxgA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,296,1580803200"; d="scan'208";a="237926017" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by fmsmga007.fm.intel.com with ESMTP; 23 Mar 2020 08:01:07 -0700 Date: Mon, 23 Mar 2020 08:01:08 -0700 From: Sean Christopherson To: syzbot Cc: alexander.deucher@amd.com, bigeasy@linutronix.de, bp@alien8.de, dave.hansen@intel.com, dvyukov@google.com, hpa@zytor.com, linmiaohe@huawei.com, linux-kernel@vger.kernel.org, mingo@redhat.com, nicholas.kazlauskas@amd.com, pbonzini@redhat.com, riel@surriel.com, sunpeng.li@amd.com, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, x86@kernel.org, zhan.liu@amd.com Subject: Re: WARNING in switch_fpu_return Message-ID: <20200323150107.GB28711@linux.intel.com> References: <000000000000f04e43059b1ee697@google.com> <000000000000ac36ba05a1793693@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <000000000000ac36ba05a1793693@google.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Mar 22, 2020 at 03:41:03PM -0700, syzbot wrote: > syzbot suspects this bug was fixed by commit: > > commit 3009afc6e39e78708d8fb444ae50544b3bcd3a3f > Author: Sean Christopherson > Date: Wed Jan 22 04:43:39 2020 +0000 > > KVM: x86: Use a typedef for fastop functions > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1667aa4be00000 > start commit: bf8d1cd4 Merge tag 'scsi-fixes' of git://git.kernel.org/pu.. > git tree: upstream > kernel config: https://syzkaller.appspot.com/x/.config?x=ed9d672709340e35 > dashboard link: https://syzkaller.appspot.com/bug?extid=f2ca20d4aa1408b0385a > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=151d549ee00000 > > If the result looks correct, please mark the bug fixed by replying with: > > #syz fix: KVM: x86: Use a typedef for fastop functions Ha, fat chance of that. The offending call to switch_fpu_return() in kvm_arch_vcpu_load() was removed by commit 2620fe268e80 ("KVM: x86: Revert "KVM: X86: Fix fpu state crash in kvm guest"") RIP: 0010:__fpregs_load_activate arch/x86/include/asm/fpu/internal.h:539 [inline] RIP: 0010:switch_fpu_return+0x437/0x4f0 arch/x86/kernel/fpu/core.c:343 kvm_arch_vcpu_load+0x66e/0x950 arch/x86/kvm/x86.c:3463 vcpu_load+0x43/0x90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:201 kvm_unload_vcpu_mmu arch/x86/kvm/x86.c:9543 [inline] kvm_free_vcpus arch/x86/kvm/x86.c:9558 [inline] kvm_arch_destroy_vm+0x184/0x5f0 arch/x86/kvm/x86.c:9663 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:816 [inline] kvm_put_kvm+0x5a5/0xcc0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:837 async_pf_execute+0x3bf/0x800 arch/x86/kvm/../../../virt/kvm/async_pf.c:101 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 So #syz fix: KVM: x86: Revert "KVM: X86: Fix fpu state crash in kvm guest" > For information about bisection process see: https://goo.gl/tpsmEJ#bisection